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Path Integral Quantization of Doubly Supersymmetric Model

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Journal of Applied Mathematics and Physics 2022年第2期10卷 245-253页

作者： Hanaa Abdulkareem Elegla nasser Ismail Farahat Physics Department Islamic University of Gaza Gaza Palestine

The Hamilton-Jacobi formalism is used to discuss the path integral quantization of the double supersymmetric models with the spinning superparticle in the component and superfield form. The equations of motion are obtained as total differential equations in many variables. The equations of motion are integrable, and the path integral is obtained as an integration over the canonical phase space coordinates.

关键词： Hamilton-Jacobi Formalism Singular Lagrangian Superparticle Superfield Supersymmetry

散斑尺寸对数字图像相关方法检测表面裂纹的影响

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中国科学技术大学学报 2022年第6期52卷 57-66,I0003页

作者： Milad Z.Aghdam nasser Soltani 德黑兰大学工程学部机械工程学院智能实验力学中心德黑兰***伊朗

数字图像相关(DIC)是一种用于无损检测的实验应力分析技术。DIC在裂纹检测中的准确性取决于多种因素,如散斑和像素的大小。本文将基于纳米粒子扩散形成的小尺寸散斑的散斑图案与传统的喷涂图案进行比较,以研究是否可以通过减小散斑和像... 详细信息

数字图像相关(DIC)是一种用于无损检测的实验应力分析技术。DIC在裂纹检测中的准确性取决于多种因素,如散斑和像素的大小。本文将基于纳米粒子扩散形成的小尺寸散斑的散斑图案与传统的喷涂图案进行比较,以研究是否可以通过减小散斑和像素的大小来改进DIC裂纹检测。由于纳米颗粒尺寸较小,使用光学显微镜对其进行放大。首先,实验研究了扩散法裂纹检测。结果表明,当裂纹边缘具有250 nm开口时,可以很容易地检测到裂纹。随后,将扩散法与使用喷涂法制备图案的传统DIC在裂纹检测方面进行了比较。结果表明,通过减小散斑尺寸和仔细分析散斑图案,此DIC技术在检测小裂纹方面明显优于传统技术。此外,传统技术更适合检测大裂纹。

关键词：无损检测裂纹检测数字图像相关

Improving low-voltage ride-through capability of a multimegawatt DFIG based wind turbine under grid faults

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Protection and Control of Modern Power Systems 2020年第1期5卷 390-402页

作者： Mohamed Nadour Ahmed Essadki Tamou nasser Research Center of Engineering and Health Science and Technologies(STIS) High Normal School of Technical Education(ENSET)Mohammed V UniversityRabatMorocco Research Center of Engineering and Health Science and Technologies Higher National School of Computer Science and Systems Analysis(ENSIAS)Mohammed V UniversityRabatMorocco

Large integration of doubly-fed induction generator(DFIG)based wind turbines(WTs)into power networks can have significant consequences for power system operation and the quality of the energy supplied due to their excessive sensitivity towards grid *** voltage dips,the resulting overcurrent and overvoltage in the rotor circuit and the DC link of a DFIG,could lead to the activation of the protection system and WT *** potentially results in sudden loss of several tens/hundreds of MWs of energy,and consequently intensifying the severity of the *** paper aims to combine the use of a crowbar protection circuit and a robust backstepping control strategy that takes into consideration of the dynamics of the magnetic flux,to improve DFIG’s Low-Voltage Ride Through capability and fulfill the latest grid code *** the power electronic interfaces are protected,the WTs also provide large reactive power during the fault to assist system voltage *** results using Matlab/Simulink demonstrate the effectiveness of the proposed strategy in terms of dynamic response and robustness against parametric variations.

关键词： Wind turbine DFIG Grid faults Crowbar protection Backstepping control Low-voltage ride through

Critical Examination of the Suitability of the Folin-Ciocalteu Reagent Assay for Quantitative Analysis of Polyphenols—The Case of Olive-Mill Wastewater

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American Journal of Analytical Chemistry 2022年第11期13卷 476-493页

作者： Mohamed Samara Ahmed nasser Uri Mingelgrin The Interinstitutional Analytical Unit The Volcani Center Rishon LeZion Israel Institute of Soils Water and Environmental Sciences The Volcani Center Rishon LeZion Israel

The suitability of the Folin-Ciocalteu reagent (FCR) and of HPLC for analyzing polyphenols is evaluated. FCR assay is commonly used although its flows, such as overestimating polyphenol content due to interference by oxidizable species, were previously reported. The wide range of oxidizable species present in biological systems seriously compromises this assay’s reliability. Adding small amounts of protein to olive-mill wastewater (OMWW) significantly increased the apparent polyphenol content indicated by the FCR assay. The commonly used “reference” polyphenol as a standard for “total polyphenols” quantification is problematic since each polyphenol responds differently to the FCR. Conversely, HPLC may underestimate polyphenol content. No single HPLC protocol is likely to detect the whole myriad of polyphenols which may be present in a polyphenol-containing system. In analyzing 5 OMWW samples both by FCR assay and HPLC, the polyphenol content indicated by the FCR assay was up to six-fold higher than that determined by HPLC.

关键词： Folin-Ciocalteu Reagent Assay HPLC Polyphenol Analysis Olive-Mill Wastewater Polyphenols

An expeditious and one-pot synthesis of unsymmetrical 2,5-disubstituted-1,3,4-oxadiazoles under microwave irradiation and solvent-free conditions

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Chinese Chemical Letters 2008年第10期19卷 1143-1146页

作者： nasser Montazeri Kurosh Rad-Moghadam Chemistry Department Azad University of TonekabonTonekabon 46841-61167Iran Chemistry Department University of GuilanRashtP.O.Box 41335-1914Iran

A one-pot synthesis of some unsymmetrical 2,5-disubstituted-1,3,4-oxadiazoles via cyclocondensation of benzoylhydrazines with orthoesters under solvent-free and microwave conditions are described here. The reaction is efficiently catalyzed by silica- supported sulfuric acid as it provided the title compounds in high yields and relatively short times. The catalyst is reusable and can be applied several times without considerable decrease in the yields and rates of the reactions.

关键词： 2,5-Disubstituted-1,3,4-oxadiazoles Silica-supported sulfuric acid Solvent-free Microwave Orthoester

Impact of COVID-19 infection during pregnancy on maternal and fetal outcomes

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Reproductive and Developmental Medicine 2023年第2期7卷 108-114页

作者： Mohamed Elsibai Anter nasser Kamal Abd El-Aal Mohamed Abd Allah Rezk Hussein Fahmy Moawad Ahmed Tharwat Abudakika Obstetrics and Gynecology Department Faculty of MedicineElkom CityMenoufia UniversityMenoufiaEgypt Resident of Obstetrics and Gynecology at al-Bagour General Hospital al-Bagour CityMenoufiaEgypt

Objectives:The objective of this study is to assess the impact of coronavirus disease 2019(COVID-19)infection during pregnancy on maternal and fetal outcome in relation to gestational ***:This retrospective study was conducted between May 2020 and July ***-five women infected with severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)and hospitalized at a quarantine hospital were ***-four women received prenatal care at the hospital until delivery,while 31 dropped out from the study due to COVID-19 recovery and discharge before ***:COVID-19 was found in 83%of the pregnant women after 20 weeks of *** most common symptoms were cough and *** complications included severe pneumonia and *** maternal mortality rate was 9.2%.Premature rupture of membranes and severe hypertension during labor affected nearly 9%of the pregnant women who completed prenatal care until delivery at the *** labor occurred at a rate of 38.2%.There were seven(20.8%)stillbirths and two cases of infant ***:Hospitalized pregnant women who have coronavirus infection,lymphopenia,and a high C-reactive protein level were at a higher risk of developing severe illness,which can lead to maternal and neonatal complications.

关键词： COVID-19 Hospitals Infant Quarantine Pregnancy outcome Prenatal care Women

A Taxonomy of Exact Methods for Partial Max-SAT

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Journal of Computer Science & Technology 2013年第2期28卷 232-246页

作者： Mohamed El Bachir Menai Tasniem nasser Al-Yahya Department of Computer Science College of Computer and Information Sciences King Saud University

Partial Maximum Boolean Satisfiability （Partial Max-SAT or PMSAT） is an optimization variant of Boolean satisfiability （SAT） problem, in which a variable assignment is required to satisfy all hard clauses and a maximum number of soft clauses in a Boolean formula. PMSAT is considered as an interesting encoding domain to many reaHife problems for which a solution is acceptable even if some constraints are violated. Amongst the problems that can be formulated as such are planning and scheduling. New insights into the study of PMSAT problem have been gained since the introduction of the Max-SAT evaluations in 2006. Indeed, several PMSAT exact solvers have been developed based mainly on the Davis- Putnam-Logemann-Loveland （DPLL） procedure and Branch and Bound （B^B） algorithms. In this paper, we investigate and analyze a number of exact methods for PMSAT. We propose a taxonomy of the main exact methods within a general framework that integrates their various techniques into a unified perspective. We show its effectiveness by using it to classify PMSAT exact solvers which participated in the 2007~2011 Max-SAT evaluations, emphasizing on the most promising research directions.

关键词： Partial Max-SAT Davis-Putnam-Logenmann-Loveland branch and bound unsatisfiability pseudo-Boolean optimization

LES of rotating film-cooling performance in a 1-1/2 turbine stage

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Propulsion and Power Research 2019年第2期8卷 85-107页

作者： Nabeel Al-Zurfi Adel nasser Mechanical Engineering Department Faculty of EngineeringUniversity of KufaNajafIraq School of Mechanical Aerospace and Civil EngineeringThe University of ManchesterManchesterM139PLUK

The large eddy simulation method was employed to investigate the film-cooling performance in a low-speed rotor blade of a 1-1/2 turbine *** rotor blade height and axial chord length were 99 mm and 124.3 mm,*** rows of film holes were placed on the rotor blade surface,one each on the pressure and suction *** row had three cylindrical film holes with a diameter of 4 mm and a tangential injection angle of 28°on the pressure side and 361 on the suction *** Reynolds number was fixed at Re=1.92×10^(5)and the coolant-to-mainstream density ratio(DR)was about *** were carried out for three different rotating speeds of 1800,2100,and 2400 rpm with the blowing ratio(BR)varying from 0.3 to *** commercial CFD code STAR-CCM+was used to run the simulations using the WALE subgrid-scale model for modelling the *** results show that on the pressure side,the film coverage and filmcooling effectiveness decrease with increasing rotation number(Ro)and increase with increasing blowing ratio(BR).A higher Ro and lower BR result in a stronger film *** film injection with higher BR produces better film *** film deflects centrifugally where the deflection becomes greater with increasing *** the suction side,the film coverage and film-cooling effectiveness increase with increasing either Ro or BR and a centripetal deflection of the film is *** deflection of the film path could be amplified by either increasing the Ro at a constant BR or decreasing the BR at a constant *** the rotation weakens the film deflection towards the hub on the suction ***,it was found that both rotation number and blowing ratio play significant roles in determining the film-cooling effectiveness distributions of the rotor blade surface.

关键词： Rotor blade Large eddy simulation Film-cooling effectiveness Turbulence Rotation Subgrid-scale

Professional values in nursing students in Jordan:baccalaureate nursing students’perception

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Frontiers of Nursing 2022年第3期9卷 319-328页

作者： Rabia S.Allari nasser I.Abu-El-Noor Mysoon K.Abu-El-Noor Faculty of Nursing Al-Ahliyya Amman UniversityJordan Faculty of Nursing Islamic University of GazaPalestine

Objective:Baccalaureate degree curricula consist of several professional values required for nursing students,which are taught in many *** study aimed to explore the perception of baccalaureate Jordanian nursing students regarding professional values and to assess the relationship between students’demographics and their perception of professional ***:The study design was a descriptive,cross-sectional correlational design.A convenience sample of 182 Jordanian undergraduate nursing students enrolled at one of the most prominent universities in Jordan who completed and submitted a self-administered Nurses’Professional Values Scale(NPVS)was considered for this ***:The NPVS total score ranged from 37 to 130,with a relatively high total score mean(99.68 with a mean of 3.83 out of 5).The highest score domain in NPVS was“Justice”with a mean of 3.97,while the lowest ranked domain was“Activism”with a mean of *** correlation coefficient showed no statistically significant correlation between age nor accumulative students’average with a total score of Nurses Professional Values Scale-revised(NPVS-R)and its *** t test results showed that gender and type of students’enrollment(regular ***)did not affect the means of NPVS-R and its *** differences were found to be statistically significant between the means of first year students and fourth year students in the total score of ***:Findings of the study alert nursing educators to pay more attention to the importance of promoting the values related to“activism”and“professionalism”among nursing *** for enhancing the roles of peer supervision and providing peer review to colleagues would contribute to improving nursing students’performance and raising self-awareness because when nursing educators pay more attention to the items of these domains,better future nursing professionals,leaders,and researchers can be ***,understanding nursin

关键词： activism caring justice nursing professional values professionalism student values trust